[GeoRoss]

You need to be a couple of hundred miles from a DGPS station that sees the same constellation of satellites.


You then need to be able to get the time log of your data off your mobile unit.

You then take the time correction info from the the DGPS station and apply that to the time data from your mobile unit.

This corrects for the unavoidable errors of atmospherics, satellites, etc. It doesn't correct for the systemic error's associated with the unit.

You can create your own DGPS station by setting up a unit at a know location.

I've never had to do this so this is just the basic work flow as colleagues have described it to me.